The present invention relates to agricultural particulate material delivery systems for delivering and applying particulate materials, such as fertilizer, seed, insecticide or herbicide to a growing medium. In particular, the present invention relates to a pneumatic agricultural particulate material delivery system.
Pneumatic agricultural particulate material delivery systems utilize pressurized air to assist in the delivery and movement of particulate material such as fertilizer, seed, insecticide or herbicide from a particulate material supply chamber to a growing medium such as soil. Such pneumatic agricultural particulate material delivery systems are commonly employed in planters, drills and a variety of other agricultural implements. Such pneumatic agricultural material delivery systems typically use pressurized air to move the particulate material through an interior passage provided by a series of elongate tubes which extend from the particulate material supply chamber to an outlet adjacent to the soil. The series of tubes includes an upper flexible hose or tube connected to the particulate material supply chamber and a lower seed tube connected to the upper flexible tube and supported adjacent to the soil. The lower seed tube is typically supported adjacent to a furrow opening disk and includes a funnel-shaped end through which the particulate flows and is deposited into the newly formed narrow furrow.
Although pneumatic agricultural particulate material delivery systems enable a more controlled delivery of particulate material to the growing medium, such pneumatic delivery systems are not without problems. For example, in many pneumatic delivery systems, the high velocity of the air stream causes the particulate material to bounce or to be blown out of the furrow. In an attempt to slow the velocity of the particulate material, some systems include a seed brake wherein a kinked tube having a relatively large air opening on the inner curved side of the tube above the kink is spliced between the upper tube and the lower tube.
Another problem associated with such pneumatic delivery systems is non-uniform air flow through the tube due to the soil partially occluding the outlet of the tube at various times to create back pressure. This back pressure suppresses air flow and particulate material delivery to prevent consistent delivery of particulate material to the soil. To eliminate such back pressure, some pneumatic delivery systems employ an air diffuser which is spliced between the upper tube and the lower tube above the furrow opening disk. The air diffuser typically comprises a cylindrical duct having a plurality of holes radially extending through the duct.
Even though such systems improve delivery of particulate material to the soil, such systems have several associated drawbacks. Both the seed brake systems and air diffuser systems require a specialized tube which must be spliced between the upper tube and the lower tube. As a result, both systems are more difficult to assemble. Both the seed brake and the air diffuser systems include tubes which extend well above the furrow opening disk. As a result, both systems require valuable space above the furrow opening disk. Moreover, both the seed brake and the air diffuser systems permit the escape of particulate material and particulate material dust through the opening or openings prior to the material reaching the soil. Because the openings of both the seed brake system and the air diffuser system extend above the furrow opening disk, the systems and the implement employing such systems wear at an accelerated rate due to the sometimes corrosive nature of the particulate material which is sprayed into the air above the furrow opening disk and above many of the other components of the implement.
Thus, there is a continuing need for a pneumatic agricultural particulate material delivery system which is easy to assemble and does not require additional parts, which does not require additional space, which minimizes or prevents the escape of particulate material prior to the particulate material reaching the soil, and/or which minimizes the damage caused by the escape of corrosive particulate material.
The present invention provides a pneumatic agricultural particulate material delivery system for delivering agricultural particulate material to a growing medium. The delivery system includes a particulate material supply chamber, a furrow opening device configured to create a furrow in the growing medium, a plurality of tubes providing an interior passage extending from the particulate material supply chamber to an outlet proximate the furrow opening device and a pneumatic pressure source pneumatically coupled to the interior passage to supply pressurized air to the interior passage to move material within the interior passage. The plurality of tubes includes an end-most material delivery tube providing the outlet. The end-most material delivery tube includes a plurality of openings extending therethrough in communication with the interior passage.
The present invention also provides a material placement tube for use with a pneumatic agricultural particulate material delivery system. The material placement tube includes an elongate unitary outer wall providing an interior passage extending along an axis and terminating at an outlet. The passage has an upper portion and a lower constricted portion between the upper portion and the outlet. The material placement tube further includes a plurality of louvered openings extending through the outer wall in communication with the interior passage.
The present invention also provides a pneumatic agricultural particulate material delivery system including a particulate material supply chamber, a furrow opening device, one or more tubes having at least one outer wall providing an interior passage extending from the particulate material supply chamber to an outlet, a pneumatic pressure source pneumatically coupled to one or more tubes to supply pressurized air to one or more tubes to move material within one or more tubes and a plurality of louvered openings extending through the outer wall and in communication with the interior passage. The louvered openings are downwardly angled towards the interior passage and towards the outlet.
The present invention also provides a pneumatic agricultural particulate material delivery system including a particulate material supply chamber, a furrow opening device including at least one disk having an upper circumferential edge and a lower circumferential edge, at least one tube having at least one outer wall providing an interior passage extending from the particulate material supply chamber to an outlet, a pneumatic pressure source pneumatically coupled to one or more tubes to supply pressurized air to one or more tubes to move material within one or more tubes and a plurality of openings extending through the outer wall and in communication with the interior passage, wherein at least one of the plurality of openings extends below the upper circumferential edge.